This web page summarizes
my observations of Ceres during the 2014 opposition. I
present solutions for H & G, for each of the six
Framing Camera "color" filter bands. Geometric albedo
versus rotation phase is presented for each band.

The two plots are based on BLG data only. JYL plot points are
based on a data file that had the wrong phase angle listed for May
8 data, so I need to update those points. The H values are in
excellent agreement, while the G values are slightly different.
This might be caused by the bad May 8 phase angle, so the JYL G
points should be updated.

Comparing two solution sets for H vs. wavelength from same data
(JYL used data with wrong phase angle for May 8 data (my
fault)).

Comparing two solution sets for G vs. wavelength from same data
(JYL used data with wrong phase angle for May 8 data (my
fault)).

Note that since both JYL and BLG analyses give the same H values
both analyses will also yield the same geometric albedos.

Note also that the pattern of a drop in G value at 915 nm suggests
that Band I effects might be responsible for the G feature.

Upper and lower traces show maximum and minimum albedos during
a rotation.

Phase Functions and Rotation
Variation

The following pairs of plots are based on the data file DR20150110
(downloadable from above link). They are based on chi-square
solutions with re-normalized SE for fluxes (given in the data
file). Re-normalization factors that yielded reduced chi-square of
~ one were typically 1.7. Outlier data were identified using the
chi-square criterion of 11, usually. All brightness variation
plots are fitted by a 3-term sinusoid model; some additional
structure can be seen by visual inspection of these plots, which
may account for part of the SE re-normalization exceeding one.

One more HG fitting is possible: since we have a rotation
variation model let's remove it from the plot of HG data! This
should reduce the scatter of points and be more representative of
the HG relation. The next pair of plots, for 649 nm data, shows
that there is a small improvement.

Before and after removal of rotation variation, showing a slight
reduction of scatter.

SOME MATERIAL BELOW HERE NEEDS TO BE UPDATED! WILL DO IN NEXT
FEW DAYS.

Albedo Spectrum

Geometric albedo spectrum for selected phases from all data to
date (Mar 20 to Jun 13), using a phase parameter G shown in
the next graph.

Dependence of phase parameter G on wavelength (WL).

Rotation Phase-Folded Light Curves

The following phase-folded albedo light curves are based on a
solution for phase effect parameter G that was solved for each band.